The present invention relates to surgical instruments for handling body tissues that are used as grafts and methods of preparing those grafts during surgery. More specifically, the invention relates to graft preparation instruments that handle grafts used to repair or replace soft tissue during surgery and methods of doing the same.
Grafting refers to a surgical procedure to move tissue (a “graft”) from one site to another in a patient's body, or from a site on a cadaver's body to a site on the patient's body. If a graft is harvested from a patient's body, it is called an autograft. If a graft is harvested from a cadaver, it is called an allograft.
Once a surgeon takes tissue out of a patient's body (i.e., harvests a graft), the graft is subject to a certain amount of preconditioning or preparation in order to be ready to be inserted back into the patient's body. Additionally, the site of the insertion into a patient's body (e.g. a patient's knee) also requires preconditioning or preparation in order to accept the graft.
Accordingly, there is much handling of the graft tissue outside of a patient's body. As such, the risk of contamination of the graft, which can lead to post-operative infection, increases each time the graft is manipulated. To reduce the risk of post-operative infection, grafts are often soaked in a solution of saline and an antibiotic (a “saline solution”) while the insertion site is being prepared. The graft may be soaked in the saline solution in a variety of way. For example, the graft may be disposed in a bowl of the saline solution or may be wrapped in gauzes soaked in the solution.
However, even though the risk of post-operative infection is small, it is always present. Therefore, there is always a need to further reduce the risk of infection from developing in a graft following surgery. Additionally, there is a need for an instrument and method, which will reduce the risk of contamination in a graft while the insertion site is being prepared to accept the graft.
The present invention offers advantages and alternatives over the prior art by providing a graft preparation instrument and method, which temporarily increases the surface area of a graft prior to being placed into a solution of saline and antibiotics. The increased surface area exposes a greater percentage of the graft to the antibiotic in order to reduce the risk of post-operative infection. The surface area of the graft could be temporarily increased by between about 20 to about 50 percent. Further, the instrument and method compresses the bulk volume of the graft prior to being placed into the solution. Once exposed to the solution, the viscoelastic properties of the graft enable the graft to return substantially to its normal shape while soaking in the solution. As such, a portion of the solution is absorbed into the graft to further reduce the risk of post-operative infection.
A graft preparation instrument in accordance with one or more aspects of the present invention includes a first mold including a plurality of first protrusions disposed on a first working surface of the first mold. The first protrusions are separated by a plurality of first spaces. A second mold includes a plurality of second protrusions disposed on a second working surface of the second mold. The second protrusions are separated by a plurality of second spaces. The first and second molds are movable from an open position of the instrument to a closed position of the instrument. In the open position, the first and second working surfaces are separated by an open position distance large enough to place a graft therebetween. In the closed position, the first and second working surfaces are separated by a closed position distance such that the first protrusions are operable to form indentations in a first surface of the graft and the second protrusions are operable to form indentations in a second surface of the graft.
A method of preparing a graft during surgery in accordance with one or more aspects of the present invention includes harvesting a graft from one of a patient's body and a cadaver. A graft preparation instrument is provided. The instrument includes a first mold having a plurality of first protrusions disposed on a first working surface of the first mold. The first protrusions are separated by a plurality of first spaces. The instrument also includes a second mold having a plurality of second protrusions disposed on a second working surface of the second mold. The second protrusions are separated by a plurality of second spaces. The first and second molds are movable from an open position of the instrument to a closed position of the instrument. In the open position, the first and second working surfaces are separated by an open position distance large enough to place a graft therebetween. In the closed position, the first and second working surfaces are separated by a closed position distance such that the first protrusions are operable to form indentations in a first surface of the graft and the second protrusions are operable to form indentations in a second surface of the graft. The method also includes placing the graft between the first and second protrusions when the instrument is in the open position. The instrument is then moved to the closed position. The surface area of the graft is increased by forming indentations in the graft with the first and second protrusions when the instrument is in the closed position.
The invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the methods, systems, and devices disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those skilled in the art will understand that the methods, systems, and devices specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the present invention is defined solely by the claims. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention.
The terms “substantially”, “approximately”, “about”, “relatively,” or other such similar terms that may be used throughout this disclosure, including the claims, are used to describe and account for small fluctuations, such as due to variations in processing. For example, they can refer to less than or equal to ±10%, such as less than or equal to ±5%, such as less than or equal to ±2%, such as less than or equal to ±1%, such as less than or equal to ±0.5%, such as less than or equal to ±0.2%, such as less than or equal to ±0.1%, such as less than or equal to ±0.05%.
Soft tissue grafts, such as autografts from a patient's body or allografts from a cadaver, are generally harvested from ligaments or tendons. The grafts are used to repair or replace other damaged soft tissue in an injured patient, such as the ligaments and tendons that connect the various joints of a human body.
By way of example, the anterior cruciate ligament (ACL), the posterior cruciate ligament (PCL) and other ligaments and soft tissue in the knee joint help to stabilize the joint during articulation activities of normal daily living. These structures hold the upper bone (femur) in relative proximity to the lower bone (tibia) as one flexes and extends their knee during mobility activities or during simple sitting and standing motions. Unfortunately, these ligaments and other soft tissues often become injured (e.g., ruptured, strained, sprained or stretched), causing pain, swelling, and joint instability. Because of the way the knee is loaded, the ACL is often the ligament in the knee that ruptures or gets damaged and needs replacement.
Thus, ligament reconstruction, such as ACL reconstruction, is routinely performed in injured patients. Often the patient's own tissues (autografts) are used to reconstruct the ACL. Typically, an autograft from the hamstrings tendons (such as the gracilis and/or semitendinosis tendons) are used to replace a ruptured or injured ACL.
In order to use a graft tissue, a surgeon must harvest the graft in-situ and prepare the graft for implantation. The preparation procedure often includes significant manipulation of the graft tissue (e.g., trimming, stretching, suturing or the like) outside the body and, thus, subjects the tissue to risk of disease and contamination leading to infection. Currently, after manipulation of a graft, surgeons will often place the prepared graft in a solution of saline and an antibiotic (for example, vancomycin or the like) in an effort to reduce the risk of contamination.
Referring to
In one aspect, the graft preparation instrument 100 includes a first mold 102 and a second mold 104 that are operatively connected to a pivotable clamping device 106. The first and second molds 102, 104 may be composed of a biocompatible material that is not toxic, injurious or physiologically reactive to living tissue. Examples of such biocompatible materials would be stainless steel, ultrahigh molecular weight polyethylene polymer or other well-known inert bio-materials.
The clamping device 106 is operable to pivot the first and second molds 102, 104 from an open position 108 (best seen in
However, though the clamping device 106 of
Referring to
The graft preparation instrument 100 includes the first mold 102 and the second mold 104. The first mold 102 includes a plurality of first protrusions 116 disposed on a first working surface 118 of the first mold 102. The first protrusions 116 are separated by a plurality of first spaces 120. The second mold 104 includes a plurality of second protrusions 122 disposed on a second working surface 124 of the second mold 104. The second protrusions 122 are separated by a plurality of second spaces 126.
The first and second molds 102, 104 are movable from the open position 108 (best seen in
The first and second protrusions 116, 122 may be disposed on their respective molds 102, 104 so that they are staggered apart. Accordingly, when the instrument 100 is in its closed position 110, the first and second protrusions 116, 122 may be meshed together such that the first protrusions 116 fit at least partially between the second spaces 126 and the second protrusions 122 fit at least partially between the first spaces 120.
As illustrated in
Also as illustrated in
The first and second molds 102, 104 are operatively connected to the pivotable clamping device 106, wherein the clamping device 106 is operable to pivot the first and second molds 102, 104 between the open position 108 and closed position 110.
The particular clamping device 106 illustrated in
The first and second base plates 136, 140 are, for example, rigidly affixed to their respective first and second molds 102, 104 with a plurality of first threaded bolts 144. However, any suitable fastening device may be used in lieu of the bolts 144. For example, clips, rivets, adhesive or the like.
The example of the clamping device 106 of
A top stop portion 156 of the top attachment 146 is disposed on an opposing end of the top clamping arm 150. The top stop portion 156 extends downward perpendicularly from the top clamping arm 150 such that it extends a predetermined distance 158 (best seen in
The clamping device 106 also includes a bottom attachment 160 disposed over the second base plate 140 and is rigidly attached thereto with a plurality of the second threaded bolts 148. The bottom attachment 160 includes a bottom clamping arm 162 extending across a width of the second base plate 140. A bottom pivot end portion 164 is disposed on one end of the bottom clamping arm 162. The bottom pivot end portion 164 rigidly connects the bottom clamping arm 162 to a second side 166 of the pivoting joint 114.
A bottom stop portion 168 of the bottom attachment 160 is disposed on an opposing end of the bottom clamping arm 162. The bottom stop portion 168 extends upward perpendicularly from the bottom clamping arm 162 such that it extends a predetermined distance 170 (best seen in
As can best be seen in
More specifically, the first and second working surfaces 118, 124 are prevented from closing past the closed position distance 130 so that the staggered first and second protrusions 116, 122 cannot pinch or pierce the tissue of the graft 200. The graft may be made up of bundles of collagen fibers. The mechanical stop 172 prevents the instrument 100 from damaging the bundles while the protrusions move the bundles around to increase the surface area of the graft 200. Also, the stiffness of the clamping device 106 can also be used to control the maximum force that is applied to the graft 200 such that, when the instrument 100 is closed, the graft 200 is not overloaded and damaged.
Referring to
Also shown in
The first and second protrusions 116, 122 have been illustrated herein as cylindrical pegs 116A, 122A (
Referring to
A method of preparing a graft 200 during surgery utilizing the graft preparation device 100 includes harvesting a graft from either a patient's body (for an autograft) or from a cadaver (for an allograft). The graft 200 may be harvested from a ligament or a tendon. More specifically, the tendon may be one of the hamstring tendons, such as the gracillis tendon or the semitendinosis tendon. Alternatively the graft may be harvested from a patella tendon to form a bone-patella tendon-bone graft.
A harvested graft 200, such as from a hamstring tendon, is often long relative to an ACL that it will replace. Accordingly, the harvested graft 200 may be folded, for example, in on itself twice and sutured together to form a quadruple bundle prior to placing the graft 200 into the instrument 100.
Once the quadruple bundle graft 200 is formed, the graft preparation instrument 100 is provided. The graft preparation instrument 100 is opened to its open position 108 and the graft 200 is placed between the first and second protrusions 116, 122.
Referring to
As illustrated in
Once the indentations 202 are imprinted into the graft 200, the instrument is moved back to the open position 108 and the graft 200 is removed from the instrument. The graft is then soaked in a solution (not shown) of saline and an antibiotic. For example, the solution may be saline and vancomycin.
Soaking the graft in a solution of saline and antibiotic may be accomplished in a variety of ways. For example, the graft may be placed in a bowl of such solution. Alternatively, the graft may be wrapped in gauzes soaked in the solution.
Additionally, an embodiment of the graft preparation instrument 100 may be capable of being clamped in the closed position 110 such that the entire instrument 100, with the graft 200 disposed therein, may be placed in a solution of saline and antibiotic. Alternatively, the instrument 100 may be constructed to contain a solution of saline and antibiotic within the instrument 100 itself, such that, when the instrument 100 is in the closed position, the graft is simultaneously indented and soaked in the solution.
Referring to
To increase the surface area of the graft 200, the first protrusions 116 imprint indentations 202 into a first surface 204 of the graft. Additionally, the second protrusions 122 imprint the indentations 202 into a second surface 206 of the graft 200.
Once the graft 200 is placed in the saline/antibiotic solution, the increased surface area enables more surface contact with the solution and the antibiotic to further reduce the risk of contamination and post-operative infection. Also, the viscoelastic properties of the graft 200 allow the graft to return to substantially its normal shape while soaking in the solution. As the compressed bulk volume increases back to its normal state, a significant portion of the solution is absorbed into the graft 200, much like a compressed sponge absorbs water as it expands. The additional solution absorbed by the graft 200 also helps to further reduce the risk of post-operative infection.
Although the invention has been described by reference to specific embodiments, it should be understood that numerous changes may be made within the spirit and scope of the inventive concepts described. Accordingly, it is intended that the invention not be limited to the described embodiments, but that it have the full scope defined by the language of the following claims.
This Application perfects U.S. Provisional Patent Application No. 62/649,827 filed on Mar. 29, 2018.
Number | Date | Country | |
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62649827 | Mar 2018 | US |